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The Martian magnetotail is largely controlled by the solar wind (SW) and is modulated by variations in the upstream drivers. However, due to the limitations of single‐spacecraft observations, the effects of SW variations on the Martian magnetotail have not been fully understood so far. Here, using Tianwen‐1 and MAVEN data, we report for the first time the rapid response of Martian magnetotail to the SW disturbance. In our study, Tianwen‐1 detected the flapping of Martian magnetotail, while MAVEN monitored disturbances in the upstream SW. The results indicate that a 20% increase (or decrease) in SW dynamic pressure and a 30° (or 50°) rotation of interplanetary magnetic field clock angle could cause the Martian magnetotail to swing rapidly. These two SW disturbances could lead to oscillations of the Martian magnetotail. This study reveals the importance of joint observations for studying the interaction between the SW and Mars. Plain Language Summary: Mars lacks an intrinsic global magnetic field and as a result solar wind (SW) interacts directly with its ionosphere and atmosphere, leading to a high dependence of the Martian induced magnetosphere on SW conditions. Understanding the interaction between the SW and Mars can provide critical information for studies of planetary evolution, especially the effect of the SW on the Martian magnetotail. In previous studies, using single satellite observations, we limit ourselves to studying some local physical processes or statistical properties. Here, based on the joint measurements by Tianwen‐1 and MAVEN, we observed the rapid response of Martian magnetotail to the SW disturbance, finding that a 20% increase (or decrease) in SW dynamic pressure and a 30° (or 50°) rotation of IMF clock angle could cause the Martian magnetotail to swing rapidly. These two SW disturbances could lead to oscillations of the Martian magnetotail. These results can help us understand the SW interaction with the Martian induced magnetosphere. Key Points: We report for the first time the rapid response of Martian magnetotail to the solar wind (SW) disturbance by using Tianwen‐1 and MAVEN dataA 20% increase (or decrease) in PSW and a 30° (or 50°) rotation of interplanetary magnetic field clock angle could cause the Martian magnetotail to swingThese two SW disturbances could lead to oscillations of the Martian magnetotail [ABSTRACT FROM AUTHOR]

Magnetic holes (MHs) are transient magnetic structures responsible for energy conversion in space plasma. Using single-spacecraft measurements from Mars Atmosphere and Volatile EvolutioN (MAVEN), the existence of MHs on Mars has been confirmed. However, due to the limitations of single-spacecraft observations, significant uncertainty also arises on the identification of the spatial scale and 3D geometry of MHs. In this study, we report a series of MHs successively detected by Tianwen-1 near the high-latitude magnetopause and by the MAVEN spacecraft near the subsolar magnetopause. The large separation between Tianwen-1 and MAVEN (∼4 R M) suggests these MHs are macroscale structures extending along the axial direction. Additionally, we observe whistler waves generated by electron perpendicular anisotropy in one of the macroscale MHs. This study is the first joint observation of Martian MHs, shedding light on the research of transient magnetic structures on Mars. [ABSTRACT FROM AUTHOR]

Magnetic hole (MH), sometimes referred to as magnetic bottle, exhibits strong magnetic fields at its neck but weak magnetic fields at its belly. Such structure has been widely reported in the solar wind and the Earth's magnetosphere, but has not been reported at Jupiter. Here, for the first time, we report two MHs in the Jupiter's magnetosphere by utilizing measurements of the Juno mission, with one existing in the dawn side and the other existing in the dusk side. We find that the electron pitch‐angle distribution inside the MHs can be either cigar‐type or pancake‐type. The cigar‐type distribution probably appears at the belly of the MH, whereas the pancake‐type distribution probably appears at the neck. Our analyses of the depression of magnetic fields inside the MHs support such a conjunction. These results have advanced our understanding of the transient structure and its related electron dynamics in the giant planets' magnetosphere. Plain Language Summary: Examining the electron pitch‐angle distribution (PAD) can help us better understand the electron dynamics in planetary magnetosphere. Up to now, there has been no report of magnetic holes (MHs) at Jupiter and thus the electron dynamics in such place is unknown. Here using the Juno measurements, we for the first time report two MHs in the Jupiter's magnetosphere. We find the PA distribution of suprathermal electrons inside the MHs can be either cigar type or pancake type, and further explain their formation processes by using a magnetic bottle model. Our study is very useful to understand electron dynamics in Jupiter's magnetosphere. Key Points: For the first time, we report magnetic holes (MHs) in the Jupiter's magnetosphereWe found both cigar and pancake distribution of electrons inside magnetic holesUsing a magnetic bottle model, we reasonably explain the formation of these two distributions and provide observation evidence [ABSTRACT FROM AUTHOR]

The tailward high‐speed flows, in which various kinetic processes and magnetic structures can be embedded, are usually produced by the magnetic reconnection in the Earth's magnetotail. Here, using high‐resolution measurements from the Magnetospheric Multiscale (MMS) mission, we report an intense current in the tailward high‐speed flow. The current density can reach ∼180 nA/m2 and is primarily carried by electrons. Taking advantage of the First‐Order Taylor Expansion (FOTE) method, we reveal that such an intense current is associated with a ribbon‐like magnetic structure. A large electric field, reaching ∼90 mV/m, is also observed at the magnetic structure. The Hall term dominates the electric field, however, the contribution from the pressure gradient term and the electron inertial term is nonnegligible and can lead to strong energy conversion (E ⋅ J > 2 nW/m3) through the synergistic action with the intense current. This study improves the understanding of the current behaviors and energy conversion associated with magnetic structures in the Earth's magnetotail. Plain Language Summary: As products of the magnetotail magnetic reconnection, the earthward and tailward high‐speed flows can be usually observed as associated with a variety of kinetic processes and magnetic structures. Here, for the first time, we report an electron‐carried intense current associated with a ribbon‐like magnetic structure in the tailward high‐speed flow, by using high‐resolution MMS data and the First‐Order Taylor Expansion (FOTE) method. Encountering a large electric field with a nonnegligible contribution from the pressure gradient term and electron inertial term, such intense current leads to a strong energy conversion at the ribbon‐like magnetic structure. This study shed light on how the intense current is associated with the ribbon‐like magnetic structure and how the strong energy conversion is driven at such a structure, which complements the knowledge of the energy conversion process in the Earth's magnetotail. Key Points: An electron‐carried intense current (J > 180 nA/m2) is observed in association with a ribbon‐like structure in the tailward high‐speed flowA large electric field, with nonnegligible contribution from pressure gradient and electron inertial term, is observed at such a structureThe intense current and large electric field work together to drive a strong energy conversion (E ⋅ J > 2 nW/m3) at this structure [ABSTRACT FROM AUTHOR]

Due to the complex structure of most frame structure, a large amount of sensor data needs to be processed for damage diagnosis, which increases the computational cost of diagnosis models and poses a serious challenge to their fast, accurate, and efficient damage diagnosis. In order to address this issue, this paper proposes a novel lightweight damage diagnosis method of frame structure for mobile devices based on convolutional neural networks. This method first uses mean filtering to process the vibration data collected by sensors, and then innovatively combines two convolutional neural network models, ShuffleNet and GhostNet, to form a new lightweight convolutional neural network model called SGNet, thereby reducing the computational cost of the model while ensuring diagnosis accuracy. In order to test the performance of the method proposed in this article, experimental research on damage degree diagnosis and damage type diagnosis is conducted by taking the frame structure provided by Columbia University as the research object, and comparative experiments of performance are conducted with MobileNet, GhostNet, and ShuffleNet. The experimental results show that the lightweight damage diagnosis method for frame structure proposed in this article not only has high damage diagnosis accuracy, but also has fewer computational parameters, when the highest accuracy is 99.8%, the computational parameters are only 1 million. At the same time, it is superior to MobileNet, GhostNet, ShuffleNet in terms of diagnosis accuracy and computational cost, so it is an effective high-precision lightweight damage diagnosis method for frame structure. [ABSTRACT FROM AUTHOR]

Two Cd/Co complexes, namely, {[Cd(Bcp)(2,2'-Bpy)(H2O)]·H2O}n (I) and {[Co(Bce)(2,2'-Bpy)]}n (II) (H2Bcp = 1,2-bis(4-carboxy-phenoxy)ethane, H2Bce = 1,3-bis(4-carboxy-phenoxy)propane, 2,2'-Bpy = 2,2'-bipyridine), have been synthesized and structurally elucidated by single crystal X-ray diffraction and thermogravimetric analysis (TGA). Both complexes feature 1D zig-zag chains decorated with 2,2'-Bpy, and the whole supramolecular architectures are stabilized by extensive π···π, C–H···π and H-bonding weak interactions. Complex I shows dual fluorescence sensing towards Fe3+ and . The fluorescence quenching mechanism was further investigated. [ABSTRACT FROM AUTHOR]

The magnetotail plasma sheet boundary layer (PSBL) is a dynamic boundary layer between the hot‐denser plasma sheet and the cold‐tenuous tail lobes. It plays an important role in exchanging mass and energy in the magnetotail. In previous studies, the local current carried by the electron beams has been well understood. The strong energy conversion (E ⋅ J, E is electric field and J is current density), however, is barely reported at the PSBL. Here, using magnetospheric multiscale mission, we find a strong dawn‐dusk current with a magnitude of 80 nA/m2 at the magnetotail PSBL. The strong current appears during crossing the PSBL and is primarily contributed by the perpendicular electron currents. Cooperating with an intense fluctuating electric field (reaching ∼40 mV/m) carried by the lower‐hybrid drift waves, this dawn‐dusk current leads to a strong energy conversion with a magnitude larger than 3 nW/m3. This study enhances the understanding of local energy‐conversion processes at the PSBL. Plain Language Summary: As a spatial boundary layer between the plasma sheet and tail lobes, the magnetotail plasma sheet boundary layer (PSBL) has been widely thought of as an important channel for mass and energy exchanged in the magnetotail. In this study, we report a strong dawn‐dusk current (J > 80 nA/m2) at the PSBL by utilizing the magnetospheric multiscale mission. Such a strong current is contributed by electron currents in the perpendicular directions and leads to strong energy conversion (E ⋅ J > 3 nW/m3) at the PSBL through the interaction with the intense electric field (E > 40 mV/m) associated with the lower‐hybrid drift waves. Our results improve the understanding of the energy conversion at the PSBL. Key Points: A strong dawn‐dusk current with a magnitude of 80 nA/m2, primarily contributed by electron currents, is observed at the magnetotail plasma sheet boundary layer (PSBL)The lower‐hybrid drift waves are observed at the PSBL and carry an intense fluctuating electric field which can reach ∼40 mV/mSuch current and electric field leads to strong energy conversion at the PSBL, with a magnitude of larger than 3 nW/m3 [ABSTRACT FROM AUTHOR]

Anti‐dipolarization fronts (ADFs), characterized by the rapid increase of the negative magnetic field Bz component, are typically formed at the leading edge of the tailward reconnection jets in the Earth's magnetotail. To date, the electron‐scale current structures, which govern the energy conversion at ADFs, are still barely understood due to the lack of high‐resolution measurements. Here, using Magnetospheric Multiscale mission, we for the first time report a tailward ADF associated with strong field‐aligned current (FAC). The FAC appears at the leading part of the ADF and its densities can reach about 200 nA/m2, which is significantly larger than those reported before. Such current is primarily contributed by the electron flow, which also forms electron beam distribution in the anti‐parallel direction. Significant energy conversion (E⋅ J, E is electric field and J is current density) is also observed at the ADF, which is mainly contributed by the FAC and the fluctuating electric fields. This study makes essential steps toward understanding the current system and the energy conversion at the ADF in the Earth's magnetotail. Plain Language Summary: Dipolarization fronts (DFs) and anti‐dipolarization fronts (ADFs) are the leading edge of the reconfigured magnetic field after reconnection, expanding earthward and tailward from the reconnection site respectively. The field‐aligned current (FAC) at DFs play crucial roles in global mass transport and energy conversion during substorm and they have been widely studied by in situ observation and simulation. However, the FAC at ADFs and the corresponding energy conversion have not been studied so for. Here, for the first time, we report an ADF associated with strong FAC using high‐resolution data from the MMS mission. We investigate the detailed features of the currents, electron distribution functions, electric fields and energy conversion at the ADF. This study shed light on how strong FAC drive energy conversion at ADFs. Key Points: We for the first time report a tailward anti‐dipolarization front (ADF) associated with strong field‐aligned current (FAC)The FAC is primarily carried by electrons and can reach ∼200 nA/m2, which is even stronger than the FACs reported in earthward Dipolarization frontsThe strong FAC and fluctuating electric fields can drive significant energy conversion at the ADF [ABSTRACT FROM AUTHOR]

Cryogenic vertical-cavity surface-emitting lasers (VCSELs) for high-speed computing and energy-efficient data links have recently received considerable interest due to the microcavity laser bandwidth enhancement at low operating power. In this work, microwave on-wafer measurements of VCSELs for frequencies up to 50 GHz are performed over temperatures down to 82 K. Subsequently, we applied parasitic de-embedding techniques to develop a microwave-optical laser model. Based on the bias-dependent measurement of laser frequency responses and laser model, the photon and electron–hole (e–h) recombination lifetimes are accurately extracted to explain the physics of laser bandwidth enhancement and the behavior of resonances. Finally, we demonstrate that the VCSEL can deliver a modulated bandwidth of >60 GHz at a low operating current, I = 3 mA, for delivering >120 Gb/s non-return-to-zero data to establish an energy-efficient optical link at 82 K. [ABSTRACT FROM AUTHOR]

The electron rolling‐pin distribution, showing electron pitch angles primarily at 0°, 90°, and 180°, has been widely studied in the Earth's magnetosphere, but has never been reported in other planetary environments. Here, by utilizing the Jupiter Near‐polar Orbiter (Juno) measurements, we report for the first time the electron rolling‐pin distribution in Jupiter's magnetosphere. We reveal the energy range of such distribution and find it appears only above 19.5 keV, falling well into the suprathermal energy range. Moreover, we quantitively reproduce the formation processes of such distribution by using an analytical model. Gratifyingly, the distribution derived from the analytical model agrees well with the Juno observations, indicating such distribution is formed by the combination of global‐scale Fermi acceleration and local‐scale betatron acceleration. These results, demonstrating that the electron rolling‐pin distribution exists beyond the Earth, can improve our knowledge of electron dynamics in planetary magnetosphere. Plain Language Summary: Examining the electron pitch angle distribution can help us better understand the electron dynamics in planetary magnetosphere. Up to now, it still remains unknown whether the rolling‐pin distribution, which shows pitch angles primarily at 0°, 90°, and 180°, exists beyond the Earth. Here using the Juno measurements, for the first time, we report such distribution in the Jupiter's magnetosphere. We find the rolling‐pin distribution appears only in the suprathermal electrons, and further explain its formation processes by using an analytical model. Our study is useful to understand electron dynamics in planetary magnetosphere. Key Points: We for the first time provide the evidence of electron rolling‐pin distribution in Jupiter's magnetosphereThe rolling‐pin distribution appears only above 19.5 keV, falling well into the suprathermal energy rangeThe rolling‐pin distribution is formed by the combination of global‐scale Fermi acceleration and local‐scale betatron acceleration [ABSTRACT FROM AUTHOR]

The Earth's magnetopause is an ion‐scale boundary that separates the magnetosphere from the shocked solar wind. At such boundary, energy‐conversion processes frequently occur. Previous studies suggested that such energy conversions are related to the magnetic reconnection process. Here, we report a new mechanism that the coaction between the twisted magnetic structure and lower‐hybrid waves can also drive energy conversion (J⋅ E, J is current density and E is electric field) at the magnetopause boundary layer, by using high‐resolution measurements of the four Magnetospheric Multiscale spacecraft. We find that such energy conversion is efficient (with magnitude up to 20 nW/m3) and is attributed to an intense current filament (j ≈ 3,800 nA/m2) and a fluctuating electric field driven by lower‐hybrid waves. With the help of the First‐Order Taylor Expansion method, we find that the intense current filament is driven by a twisted magnetic structure at electron scale. Our study improves the understanding of energy‐conversion processes at the Earth's magnetopause. Plain Language Summary: Solar wind‐magnetosphere coupling is a key process during the solar‐terrestrial energy chain and the space weather forecast. A significant amount of the solar wind energy is converted at the Earth's magnetopause, and thus, uncovering the mechanism of energy‐conversion processes is of key importance in understanding such a coupling process between solar wind and magnetosphere. Here, we report a new mechanism that the coaction between the twisted magnetic structure and fluctuating electric field can also drive energy conversion. It's found that the energy conversion is efficient and is attributed to an intense current filament driven by the twisted magnetic structure and a fluctuating electric field provided by lower‐hybrid waves. Key Points: An intense current filament (up to 3,800 nA/m2) accompanied by energy conversion (up to 20 nW/m3) are observed at the magnetopause boundary layerThe intense current filament is driven by an electron‐scale twisted magnetic structureThe energy conversion at the current filament is driven by the coaction between the twisted magnetic structure and the lower‐hybrid waves [ABSTRACT FROM AUTHOR]

1. Infectious injury caused by lipopolysaccharide (LPS), a metabolite of gram-negative bacteria, can induce stress responses in animals and is a significant cause of morbidity and mortality in young birds. The purpose of this study was to investigate the effects of dietary supplementation with oleanolic acid (OA) on acute liver injury in broiler chickens challenged with LPS. 2. In total, 120 broiler chickens were randomly divided into six groups and fed a basal diet containing 0, 50, 100, or 200 mg/kg OA or 100 mg/kg aureomycin. On d 15, broiler chickens were injected with either LPS or an equivalent volume of normal saline. Six hours after LPS injection, two broiler chicks were randomly selected for sampling in each replicate. 3. The results indicated that dietary aureomycin was ineffective in alleviating LSP-associated liver injury, but protected broiler chickens from LPS-induced liver damage. This promoted a significant reduction in the levels of malondialdehyde and an increase in the levels of superoxide dismutase in liver. In addition, OA was found to cause significant reductions in the relative expression of IL-1β, IL-6, and TNF-α in broiler liver tissues, whereas the relative expression of IL-10 was significantly increased. 4. In conclusion, oleanolic acid can alleviate oxidative stress and injury in the livers of broiler chickens induced by lipopolysaccharide. Consequently, oleanolic acid has potential utility as a novel anti-inflammatory and antioxidant feed additive. [ABSTRACT FROM AUTHOR]

This paper proposes a coupling model for evaluating the occurrence of piping erosion under free flow and seepage flow. The model employs the Navier–Stokes equation to describe free water flow in a pore channel and the Brinkman-extended Darcy equation to describe seepage flow in soft soils. The expression of the critical hydraulic gradient of piping erosion was derived based on the force limit equilibrium of a single soil particle within the pore channel. The results of the theoretical calculation of the proposed model are in good agreement with the results obtained by two classical piping tests. However, compared with existing formulas, the proposed formula has better generalization and accuracy. Moreover, the critical hydraulic gradient varies linearly with the soft soil porosity (negative correlation), the soil particle diameter (positive correlation) inside the pore channel, and the stress jump coefficient (positive correlation) at the interface between the pore channel and the soft soils. [ABSTRACT FROM AUTHOR]

The wettability of metal surfaces is of importance in different practical applications. In the present work, we investigated the role of alumina coatings in the variation of the surface wettability of aluminum alloys by nanosecond laser ablation. The superhydrophilic surface (water contact angle close to 0°) was successfully prepared, and the superhydrophilic surface was transformed into the superhydrophobic surface (water contact angle of about 151.4°) after non-fluorinated N-octyltriethoxysilane (OcTES) treatment. XPS results showed that the Al–OH (–OH) hydrophilic groups generated by coating decomposition occupied the main regions on the surface after laser ablation. After OcTES treatment, the OcTES molecules formed Si–O–Al bonds with the rough surface, which significantly increased the C–C(H) hydrophobic groups of the surface. The superhydrophobic surface showed good self-cleaning, anti-icing and anti-corrosion properties. The fabrication method is fast, non-toxic and environmentally friendly, which makes it potentially useful for engineering applications. [ABSTRACT FROM AUTHOR]

The electron butterfly distribution, characterized by pitch angles (PA) primarily at 45° and 135°, was rarely observed in Earth's magnetotail. Here using the high‐resolution measurements from Magnetospheric Multiscale mission, we present the observation of electron butterfly distribution in a contracting dipolarization front (DF), and propose a new physical mechanism to explain its formation. Specifically, we discover that the electron butterfly distribution only exhibited in the locally contracted DF and was observed above 1.7 keV. We infer that local contraction of the DF transformed its configuration from a magnetic bottle to an hourglass‐shaped magnetic structure, and the butterfly distribution was formed by the magnetic mirror effect of this magnetic hourglass. Additionally, the theoretically estimated loss cone of the magnetic hourglass fits well with the observations of electrons, validating our inference about the formation mechanism. These findings can improve our understanding of electron dynamics in Earth's magnetosphere. Plain Language Summary: Examining the pitch‐angle (PA) distribution of electrons can help us understand the electron dynamic process in space. In this paper, we present the observation of electron butterfly distribution, characterized by PA primarily around 45° and 135°, in Earth's magnetotail. We find that the electron butterfly distribution was observed only above 1.7 keV, and exhibited in a locally contracting dipolarization front (DF). We propose a new formation mechanism for this distribution, and perform the theoretical calculations to validate it. Our findings can significantly improve the knowledge of electron dynamics in Earth's magnetosphere. Key Points: The electron butterfly distribution was observed above 1.7 keV and only exhibited in the contracted dipolarization front (DF)The local contraction of the DF transformed its configuration from a magnetic bottle to an hourglass‐shaped magnetic structureThe butterfly distribution is formed by the magnetic mirror effect of the hourglass‐shaped structure [ABSTRACT FROM AUTHOR]

Based on the structural characteristics of bird-wing bifurcation, the blade tip groove structure of a linear compressor cascade for controlling separation of suction corner was studied with the use of numerical calculation. The obtained results indicated that the effects of the tip groove on the aerodynamic performance and the flow field structure could be improved. The tip groove design caused high-pressure fluid to be injected into the corner position of separation, causing the initial corner position of separation to move backward, so the pitchwise and spanwise corner separation to be controlled. Under the conditions of positive angle of incidence, the blade tip groove had a good loss reduction effect. When the angle of incidence was less than the angle of incidence with the minimum loss, the flow loss in the cascade increased by the adoption of the tip groove. The tip groove needed to be installed near the initial position of the corner separation. As in the groove height increases, the suppression effect of the tip groove on the corner separation initially increases and then decreases. When the groove height is equal to 4% of the blade height (H), the flow loss in the cascade reduces by 14.42%. [ABSTRACT FROM AUTHOR]

To validate the large plate cutting schemes of Hybrid OLED, we conducted experiments, and evaluated the applicability and limitations of Wheel Cutting, Bessel Laser Cutting and Laser scribing from the break rate, bending strength and processing efficiency dimensions. The conclusions provide an important experimental foundation and technical scheme for the cutting scheme of Hybrid OLED and the glass coated with a multi‐layer. [ABSTRACT FROM AUTHOR]

In this paper, to address the cooperative localisation of a heterogeneous UAV swarm in the GNSS-denied environment, an adaptive simulated annealing-particle swarm optimisation (SA-PSO) cooperative localisation algorithm is proposed. Firstly, the forming principle of the communication and measurement framework is investigated in light of a heterogeneous UAV swarm composition. Secondly, a reasonably cooperative localisation function is established based on the proposed forming principle, which can minimise the relative localisation error with limited available information. Then, an adaptive weight principle is incorporated into the particle swarm optimisation (PSO) for better performance. Furthermore, in order to overcome the drawbacks of PSO algorithm easily falling into the local extreme point, an adaptive SA-PSO algorithm is improved to promote the convergence speed of cooperative localisation. Finally, comparative simulations are performed among the adaptive SA-PSO, adaptive PSO, and PSO algorithms to demonstrate the feasibility and superiority of the proposed adaptive SA-PSO algorithm. Simulation results show that the proposed algorithm has better performance in convergence speed, and the cooperative localisation precision can be guaranteed. [ABSTRACT FROM AUTHOR]

Surface runoff is an important factor inducing soil erosion of shallow slope. Due to the complexity of material composition, grain arrangement and porosity structure, however, it is difficult to directly give the critical shear velocity of incipient motion under surface runoff if all matters of cohesive sediment are taken into account. Considering the bonding effect of cohesive sediment, a closed-form solution for critical shear velocity is presented in this work. Three primary assumptions, i.e., slope angle less than 30 deg, laminar for surface runoff and uniform film water around soil particles, are made in deriving the solution. The bonding force of cohesive sediment stemming from film water contact can be embedded in the force analysis of single particle. Laboratory scouring test results validate the present solution. [ABSTRACT FROM AUTHOR]

With the rapid economic growth since the turn of the 21st century, the fast-degrading environment has emerged as a significant factor limiting the continued development of megacities such as Beijing and Shanghai. It has also placed unprecedented pressure on ecosystem services. Therefore, the present study uses the morphological spatial pattern analysis model and the index of connectivity (IIC) and possible connectivity (PC) indices to analyse changes in the spatial pattern of Beijing and combines the carbon sequestration module and habitat quality module of the InVEST model to evaluate the supporting functions of Beijing's ecosystems from 2000 to 2020, to investigate the characteristics of spatial and temporal changes and the drivers of these changes, and to provide a scientific basis for urban ecosystem management. The results show that between 2000 and 2020, the overall area of green space in Beijing decreased, and the IIC and the index of PC decreased, indicating that the overall spatial connectivity of green space decreased and fragmentation increased. During this period, the carbon stock within the Beijing city area decreased by a total of about 2.94 Tg, and the habitat quality index decreased from 0.71 to 0.67, indicating a trend of degradation. This paper suggests that the expansion of urban and rural land use is a major factor in the decline of ecosystem support services, while the spatial pattern of the landscape also has an impact on habitat quality, which is generally higher in areas with better landscape connectivity. [ABSTRACT FROM AUTHOR]

Calls have been made for water and ecological planning and design to tackle the ongoing environmental degradation, yet the gaps are not clear where the implemented water (blue) and ecological (green) infrastructure might help to improve the ecosystem services. We selected mega-city Beijing, the pioneer of the "Ecological Priority" strategy, as the study area. We evaluated the conformance and performance of Beijing's water-related ecological planning implementation on ecological effectiveness from 2000 to 2015. The morphological spatial pattern analysis (MSPA) method was used to extract the blue-green ecological source areas to conform with blue-green plannings. Support, regulation and supply ecosystem services were simulated to integrate ecological effectiveness and its temporal-spatial dynamics. The results show a gradual increase in the proportion of spatial conformance, which remained higher than that of spatial low conformance. The trend of the performance of the implementation based on the analysis of ecosystem services decreased. Our results will help inform upcoming actions related to blue-green planning and management in mega-cities. [ABSTRACT FROM AUTHOR]

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Two new cobalt(II) coordination complexes [Co(Phtpy)(HBTC)0.5]n·nH2O (I) and [Co(Meophtpy)(HBTC)0.5]n·nH2O (II) (Phtpy = 4'-(4-phenyl)-3,2':6',3''-terpyridine, Meophtpy = 4'-(4-methoxyphenyl)-3,2':6',3''-terpyridine,H3BTC = trimesic acid) were synthesized under solvothermal conditions. The structures of complexes I, II have been characterized by elemental analysis, FT-IR, TG analysis, PXRD and single crystal X-ray diffraction techniques (CCDC nos. 2123289 (I) and 2123290 (II)). For complex I, a two-dimensional (2D) layered structure is formed parallel to the bc plane and the adjacent layers are connected by Phtpy ligand along a direction to form a three-dimensional (3D) structure. It is represented as 2-nodal (3, 5)-connected {4.6.8}{4.66.83} by Schläfli symbol. For complex II, one-dimensional (1D) ladder chains along two almost perpendicular directions are formed and these chains are connected by Meophtpy ligands to form a 3D structure. It is represented as 2-nodal (3, 5)-connected {42.65.83}{42.6} by Schläfli symbol. In both complexes, dominant antiferromagnetic interactions between Co(II) ions were observed. [ABSTRACT FROM AUTHOR]

Vertical placement of the lateral portion of a wellbore in shale formations is crucial for the optimization of hydraulic fracture geometry and the resultant well production. It is common to design the trajectory of a well specifically to target a certain zone in the formation. However, the variations of the vertical positions of individual stages relative to the pay zone thickness along the horizontal section are generally overlooked. Such variations are a combined effect of the 3D trajectory of the well and the dips in the reservoir layers. Using field data from the Hydraulic Fracturing Test Site 1 (HFTS 1) experiment, we reveal that along a single horizontal well, a relatively minor variation of vertical locations among the stimulation stages can induce quite significant differences in the resultant fracture geometries. We also conduct field-scale numerical simulations to further study this phenomenon. Specifically, we incorporate the reservoir's layering information in the geomechanical model by considering the relative distance between the landing point of each stage and the surface of the 3D geological layers. Through high-fidelity simulations, our study shows that the variations of stages' relative vertical positions, even within a small range, can lead to distinct fracture geometries within the same well. Results from this study can inform practical methods to design well trajectories more precisely and optimize hydraulic fractures stagewise. Highlights: Combined field tests, core sample observations, log data, microseismic mapping, and high-fidelity simulations. Accounted for hydraulic fracture swarming effects in field-scale simulations through upscaling modeling approach. Revealed small variations of stages' relative vertical positions can lead to distinct fracture geometries. Provided motivation and workflow for precise well placement and stagewise optimization based on relative vertical depth. [ABSTRACT FROM AUTHOR]

B Introduction: b Linperlisib, a PI3K inhibitor, has shown clinically efficacy and manageable safety profile as third- or further-line treatment in patients with R/R FL from a multicenter phase 2 trial (NCT04370405). [Extracted from the article]

Early life lead (Pb) exposure is detrimental to neurobehavioral development. The quality of the environment can modify negative influences from Pb exposure, impacting the developmental trajectory following Pb exposure. Little is known about the molecular underpinnings in the brain of the interaction between Pb and the quality of the environment. We examined relationships between early life Pb exposure and living in an enriched versus a non-enriched postnatal environment on genome-wide transcription profiles in hippocampus CA1. RNA-seq identified differences in the transcriptome of enriched vs. non-enriched Pb-exposed animals. Most of the gene expression changes associated with Pb exposure were reversed by enrichment. This was also true for changes in upstream regulators, splicing events and long noncoding RNAs. Non-enriched rats also had memory impairments; enriched rats had no deficits. The results demonstrate that an enriched environment has a profound impact on behavior and the Pb-modified CA1 transcriptome. These findings show the potential for interactions between Pb exposure and the environment to result in significant transcriptional changes in the brain and, to the extent that this may occur in Pb-exposed children, could influence neuropsychological/educational outcomes, underscoring the importance for early intervention and environmental enrichment for Pb-exposed children. [ABSTRACT FROM AUTHOR]

A surrogate model is an engineering method to predict the outcome of some process rather than model the real process itself. Here, we use surrogate models based on the machine learning that have been trained using a synthetic data set generated by a numerical model. The concept of a surrogate model is a powerful link between the traditional paradigm of numerical modeling and the new paradigm of machine learning. Surrogate models can provide results in seconds and predict a set of outputs of a complex process for a range of input parameters with an accuracy greater than 99%. This has an advantage over numerical models, that may need hours to attain the same accuracy. Surrogate models can be used for probabilistic analysis, numerical pre-conditioning, training and education, and for application by field practitioners. Machine learning has seen rapid growth in the last 10 years with the advent of large data sets and powerful new techniques. There is currently a unique opportunity to apply data science and machine learning methodologies as a complement to advanced numerical modeling of the subsurface. This paper describes a practical methodology for training surrogate models and gives three examples. The examples include predicting the crushed zone size in rock blasting, the effective properties of a discrete fracture network (DFN), and the bearing capacity of a layered soil. We show that surrogate models perform well when feature engineering (the application of domain knowledge to machine learning) is applied and when the number of input parameters is limited. Highlights: A methodology for creating rock and soil mechanics surrogate models is presented along with practical examples. Synthetic data sets describing the rock blasting crushed zone, the bearing capacity of layered soils, and the effective properties of discrete fracture networks are generated using numerical models. Artificial neural networks are able to rapidly and accurately predict some aspects of the numerical model results. The number of synthetic data points needed is problem dependent and a methodology to ensure accurate results over the entire target range is presented. [ABSTRACT FROM AUTHOR]

In this article, a novel winding switching control strategy is proposed to extend the speed range of a consequent-pole ferrite-permanent magnet hybrid-excited machine (CPFPM-HEM) for electric vehicle application. The key is that in low-speed range, the ac armature winding and dc field winding are connected in series to achieve large starting torque, while in high-speed range, dc field winding is injected with adjustable dc currents to realize variable speed constant voltage of ac armature winding. Furthermore, consequent-pole rotor is used to reduce the usage of the permanent magnet (PM). In the meantime, ferrite PMs are used to replace rare-earth PMs to reduce the cost with the shortage of rare-earth resources. In this article, the machine configuration, operation principle with dual excitation sources, flux modulation principle, and winding switching strategy are illustrated in detail. Then, the electromagnetic performance of the CPFPM-HEM in different speed ranges is investigated. Finally, the speed range extension with winding switching strategy is verified by the Maxwell/Simplorer co-simulation. [ABSTRACT FROM AUTHOR]

The rolling-pin distribution of suprathermal electrons, exhibiting electron pitch angles primarily at 0°, 90°, and 180°, receives attention in both observations and simulations recently. However, its formation mechanism has rarely been studied. In this work, we report an observation of such distribution with two substructures behind the dipolarization front (DF) and reveal that only Fermi mechanism is contributory to suprathermal electron acceleration. We present a new explanation for its formation. The Fermi mechanism accelerates parallel and antiparallel suprathermal electrons, the spatially varying magnetic bottles control the emergence of perpendicular electrons, and electrons whose pitch angle around 45° and 135° drift away in the middle magnetotail. Under the combination of these mechanisms, the rolling-pin distribution with two substructures is formed behind DFs. This formation mechanism is useful to understand the electron dynamics behind DFs. [ABSTRACT FROM AUTHOR]

Two Zn(II) and Cu(II) complexes formulated as Zn(DMS)(bix)0.5 (1) and Cu(DMS)(bix)0.5 (2) (DMS = 2,2-dimethylsuccinate; bix = 1,4-bis(imidazol-1-ylmethyl)benzene) are successfully prepared under hydrothermal conditions. The single crystal X-ray diffraction (XRD) analysis shows that both complexes are isostructural, have the P2/c space group and a 2D layer architecture with the DMS bisbridged ribbon. The title complexes are characterized by single crystal XRD, IR spectroscopy, TG and elemental analyses, and photoluminescence sensing in the solid state. In addition, the sensing efficiency of nitrobenzene for 1 is evaluated. [ABSTRACT FROM AUTHOR]

The combination of high-quality factors and small mode volumes in whispering-gallery-mode (WGM) resonators promotes significantly enhanced light-matter interactions, making them excellent cavities for achieving compact semiconductor lasers with low threshold and narrow linewidth. However, success in developing GaN-based WGM lasers has been extremely limited due to the complicated design and fabrication of both high-finesse optical cavities and effective efficient injection schemes. Here, we report on WGM emission from vertical-injection blue-light emitting InGaN/GaN thin-film microdisks achieved by wafer bonding and laser liftoff removal of the sapphire substrate. The observed WGMs, identified as a combination of first order and higher order modes with the aid of finite-difference time-domain simulations, have Q-factors as high as 3700. This work presents a viable approach toward the practical implementation of compact InGaN/GaN microdisk lasers through a simple and scalable process. [ABSTRACT FROM AUTHOR]

Purpose: To explore the effects of the intervening measure targeting myeloid differentiation 2 (MD2) on breast cancer progression in vitro and in vivo. Methods: The expression of MD2 in normal breast cells (Hs 578Bst) and three kinds of breast carcinoma cell lines (MCF-7, MDA-MB-231 s and 4T1) were detected by western blot. MTT assay was used to detect the proliferation of 4T1 cells treated by L6H21, cell migration and invasion was measured by wound healing assay and trans-well matrigel invasion assay, respectively. In addition, to further study the role of MD2 in tumor progression, we assessed the effects of inhibition of MD2 on the progression of xenograft tumors in vivo. Results: The expression of MD2 is much higher in MDA-MB-231 s and 4T1cells than that in normal breast cells (Hs 578Bst) or MCF-7 cells (p < 0.05). In vitro, suppression of MD2 by L6H21 has a significant inhibition of proliferation, migration and invasion in 4T1 cells in dose-dependent manner. In vivo, L6H21 pretreatment significantly improved survival of 4T1-bearing mice (p < 0.05). Additionally, we also observed that none of the mice died from the toxic effect of 10 mg kg−1 L6H21 in 60 days. Conclusion: Overall, this work indicates that suppression of MD2 shows progression inhibition in vitro and significantly prolong survival in vivo. These findings provide the potential experimental evidence for using MD2 as a therapeutic target of breast carcinoma. [ABSTRACT FROM AUTHOR]

Venation type is an important trait for terrestrial plant leaves. Especially the midvein plays a crucial role in water and nutrient transportation and correlates with leaf tolerance to physical damage. In our study, we explored the leaf tolerance to midvein damages in 95 terrestrial species by a simple midvein cut-off trial. Within three months, no detectable changes of leaf intactness were found for over two-thirds of the selected species. In two species, Acer rubrum and Hylotelephium erythrostictum, over 10 % of the leaf area was damaged by the end of the experiment. The diameter of the midvein and the leaf length showed a significantly positive correlation with the ratio of lamina damaged area to the total area (RLD), but the correlation became insignificant after including the phylogenetic relationships. The RLD varied considerably within each venation type (netted or parallel) while showed no significant difference and did not differ significantly between the two venation types; however, the RLD tended to be higher in herbaceous plants than in shrubs and trees. Our results indicated that the leaf tolerance to physical damages on the midvein of terrestrial plants was a trait somehow independent of phylogenetic relationships. [ABSTRACT FROM AUTHOR]

Due to the flux leakage and large detent force, the thrust force ripple of transverse-flux linear motor is relatively large, which restricts its further application. Also, the field of most existing transverse-flux machines is hard to be altered and regulated considering the permanent magnet (PM) excitation. Therefore, to suppress the force ripple and strengthen the flux regulation capability of transverse-flux machines, a novel hybrid excitation transverse-flux tubular motor with complementary structure is proposed in this article. The key is that a complementary and parallel structure is constructed in this motor, and hybrid excitation of both dc windings and small auxiliary PMs installed at opening of the slot is adopted in this motor as well. In addition, unequal teeth design of dc winding and ac winding is also employed to increase the thrust force density. Finite element calculation results verify the effectiveness of the proposed machine. [ABSTRACT FROM AUTHOR]

Vernier permanent-magnet (VPM) machines which have high torque density and high efficiency have been extensively used in direct drive. This article attempts to propose a new winding form and compare it with a traditional winding form as a part of fractional slot winding in the VPM machines to provide a design guideline in the aspect. Different winding forms are compared with the same copper loss and the same design. The design guideline of winding forms is provided by multiobjective generation algorithm (GA) optimization. Maximum torque value and minimum torque ripple are the optimization objectives in the GA optimization process. In addition, several models of the modularized motor with the new winding form based on the fractional-slot windings are compared, and the suitable application range of these models are discussed. [ABSTRACT FROM AUTHOR]

Two novel compounds [Zn(bitmb)(L)]·2H2O and [Co(bitmb)(L)]·2H2O are prepared under hydrothermal conditions (bitmb = 1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene; H2L = 1,3-bis-(4-carboxy-phenoxy)propane) and characterized by the single crystal X-ray diffraction analysis. Both complexes are isostructural and contain 3-fold right-handed helical 1D chains. IR and PXRD spectra, TG curves, and photoluminescent properties are also studied. [ABSTRACT FROM AUTHOR]

The stability of shallow soil slope was analyzed considering the wetting front within the slope during rainfall. The slope failure model (composed of an upper arc, a straight part in the middle, and a lower arc) was determined according to the unsaturated soil mechanics and Mohr-Coulomb criterion. The drag force due to slope runoff was embedded in the calculation of safety factor. The failure mode in this paper can be degraded to the classical circular failure mode and infinitely long slope failure mode. The experimental results are in good agreement with the theoretical values. The investigations show that the safety factor of slope decreases with increase in soil saturation and runoff depth. [ABSTRACT FROM AUTHOR]

The formation of trench defects is observed in 160nm-thick InxGa1-xN epilayers with x ≤ 0.20, grown on GaN on (0001) sapphire substrates using metalorganic vapour phase epitaxy. The trench defect density increases with increasing indium content, and high resolution transmission electron microscopy shows an identical structure to those observed previously in InGaN quantum wells, comprising meandering stacking mismatch boundaries connected to an I1-type basal plane stacking fault. These defects do not appear to relieve in-plane compressive strain. Other horizontal subinterface defects are also observed within the GaN pseudosubstrate layer of these samples and are found to be pre-existing threading dislocations which form half-loops by bending into the basal plane, and not basal plane stacking faults, as previously reported by other groups. The origins of these defects are discussed and are likely to originate from a combination of the small in-plane misorientation of the sapphire substrate and the thermal mismatch strain between the GaN and InGaN layers grown at different temperatures. [ABSTRACT FROM AUTHOR]

Elastic constants of hexagonal ScxGa1-xN and ScxAl1-xN up to x = 0.375 were calculated using a stress-strain approach. C11, C33, C44, and C66 decreased while C12 and C13 increased slightly with increasing x. The biaxial [0001] Poisson ratios increased from 0.21 for GaN to 0.38 for Sc0.375Ga0.625 N and from 0.22 for AlN to 0.40 for Sc0.375Al0.625N, due to greater u values, in-plane bond lengths and bond ionicities. Subsequently, critical thicknesses for stress relaxation were calculated for ScxAl1-xN/AlN, ScxGa1-xN/GaN, and ScxAl1-xN/GaN heterostructures using an energy balance model. These range from 2 nm for Sc0.375Al0.625N/AlN and Sc0.375Ga0.625N/GaN to infinity for lattice-matched Sc0.18Al0.82N/GaN. [ABSTRACT FROM AUTHOR]

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In explosive pollination, many structures and mechanisms have evolved to achieve high‐speed stamen movement. The male flower of the submerged plant Hydrilla verticillata is reported to be able to release pollen explosively some time after leaving the mother plant time, but the mechanism of stamen movement and the related functional structure in this species are unclear.In this study, we observed the male flower structure and pollen dispersal process of H. verticillata. We analysed the stamen movements during the pollen dispersal process and conducted several controlled experiments to study the process of storage and release of elastic potential energy in explosive pollination.When the male flower of H. verticillata is bound to the united bracts, the sepals accumulate elastic potential energy through the expansion of basal extensor cells. After the male flower is liberated from the mother plant, the stamens unfold rapidly with the sepals under adhesion and transfer the elastic potential energy to the filament in seconds. Once stamens unfold to a critical angle, at which the elasticity of the filament just exceeds the adhesion between sepals and anthers, the stamens automatically rebound and release pollen in milliseconds.These results reveal that Catapult‐like stamens, spoon‐shaped sepals and enclosed united bracts in the spathe together constitute the functional structure in rapid stamen movement of H. verticillata. They ensure that the pollen can be released on the water surface, and thus adapt successfully to the pollen‐epihydrophilous pollination. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to optimize the design of a dual-structure permanent magnet (PM) machine for the low-speed application. Multi-objective optimization using nondominated sorting genetic algorithm II (NSGA-II) is used to maximize the torque and efficiency while reducing the torque ripple of the machine. The torque, torque ripple, and efficiency of the optimized machine have significant improvement by optimizing the machine parameters within a fixed outer axial and radial length. This optimization process can be used to select the best machine design in different aspects’ requirement. [ABSTRACT FROM AUTHOR]

The fraction and distribution characteristics of phosphorus in the sediments of Sancha Lake were studied using the SMT Phosphorus fraction method and its influencing factors were discussed. According to the research results, total phosphorus (TP) content in the sediments was 270.00-3,722.80 μg·g-1, the organophosphorus (OP) content was 64.00-774.43 μg·g-1, the inorganic phosphorus (IP) content, a main phosphorus fraction, was 164.00-3,006.99 μg·g-1, accounting for about 69.32% of TP, the HCl-P content, a main phosphorus fraction of IP, was 125.00-2,474.04 μg·g-1, accounting for about 69.19% of IP, and the NaOH-P content was less, i.e. 51.00-689.72 μg·g-1, accounting for about 30.73% of IP. Different phosphorus fractions had obvious temporal and spatial variation; all the sampling sites showed a general trend where the phosphorus fraction content was higher in winter and lower in summer, similar in spring and autumn. The content of organic matter in the sediments had significant correlation with OP, NaOH-P had significant correlation with Fe in the sediments, between HCl-P in the sediments had significant correlation with Ca, APA had significant positive correlation with OP. However, the pH, TN, dissolved oxygen and temperature had no significant correlation with various phosphorus fractions. [ABSTRACT FROM AUTHOR]